qemu/target/microblaze/op_helper.c
Richard Henderson e98651d9ca target/microblaze: Unwind properly when raising divide-by-zero
Restore the correct pc when raising divide-by-zero.  Also, the
MSR[DZO] bit is sticky -- it is not cleared with a successful divide.

Tested-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2020-09-01 07:41:38 -07:00

444 lines
11 KiB
C

/*
* Microblaze helper routines.
*
* Copyright (c) 2009 Edgar E. Iglesias <edgar.iglesias@gmail.com>.
* Copyright (c) 2009-2012 PetaLogix Qld Pty Ltd.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, see <http://www.gnu.org/licenses/>.
*/
#include "qemu/osdep.h"
#include "cpu.h"
#include "exec/helper-proto.h"
#include "qemu/host-utils.h"
#include "exec/exec-all.h"
#include "exec/cpu_ldst.h"
#include "fpu/softfloat.h"
void helper_put(uint32_t id, uint32_t ctrl, uint32_t data)
{
int test = ctrl & STREAM_TEST;
int atomic = ctrl & STREAM_ATOMIC;
int control = ctrl & STREAM_CONTROL;
int nonblock = ctrl & STREAM_NONBLOCK;
int exception = ctrl & STREAM_EXCEPTION;
qemu_log_mask(LOG_UNIMP, "Unhandled stream put to stream-id=%d data=%x %s%s%s%s%s\n",
id, data,
test ? "t" : "",
nonblock ? "n" : "",
exception ? "e" : "",
control ? "c" : "",
atomic ? "a" : "");
}
uint32_t helper_get(uint32_t id, uint32_t ctrl)
{
int test = ctrl & STREAM_TEST;
int atomic = ctrl & STREAM_ATOMIC;
int control = ctrl & STREAM_CONTROL;
int nonblock = ctrl & STREAM_NONBLOCK;
int exception = ctrl & STREAM_EXCEPTION;
qemu_log_mask(LOG_UNIMP, "Unhandled stream get from stream-id=%d %s%s%s%s%s\n",
id,
test ? "t" : "",
nonblock ? "n" : "",
exception ? "e" : "",
control ? "c" : "",
atomic ? "a" : "");
return 0xdead0000 | id;
}
void helper_raise_exception(CPUMBState *env, uint32_t index)
{
CPUState *cs = env_cpu(env);
cs->exception_index = index;
cpu_loop_exit(cs);
}
static bool check_divz(CPUMBState *env, uint32_t a, uint32_t b, uintptr_t ra)
{
if (unlikely(b == 0)) {
env->msr |= MSR_DZ;
if ((env->msr & MSR_EE) &&
env_archcpu(env)->cfg.div_zero_exception) {
CPUState *cs = env_cpu(env);
env->esr = ESR_EC_DIVZERO;
cs->exception_index = EXCP_HW_EXCP;
cpu_loop_exit_restore(cs, ra);
}
return false;
}
return true;
}
uint32_t helper_divs(CPUMBState *env, uint32_t a, uint32_t b)
{
if (!check_divz(env, a, b, GETPC())) {
return 0;
}
return (int32_t)a / (int32_t)b;
}
uint32_t helper_divu(CPUMBState *env, uint32_t a, uint32_t b)
{
if (!check_divz(env, a, b, GETPC())) {
return 0;
}
return a / b;
}
/* raise FPU exception. */
static void raise_fpu_exception(CPUMBState *env)
{
env->esr = ESR_EC_FPU;
helper_raise_exception(env, EXCP_HW_EXCP);
}
static void update_fpu_flags(CPUMBState *env, int flags)
{
int raise = 0;
if (flags & float_flag_invalid) {
env->fsr |= FSR_IO;
raise = 1;
}
if (flags & float_flag_divbyzero) {
env->fsr |= FSR_DZ;
raise = 1;
}
if (flags & float_flag_overflow) {
env->fsr |= FSR_OF;
raise = 1;
}
if (flags & float_flag_underflow) {
env->fsr |= FSR_UF;
raise = 1;
}
if (raise
&& (env->pvr.regs[2] & PVR2_FPU_EXC_MASK)
&& (env->msr & MSR_EE)) {
raise_fpu_exception(env);
}
}
uint32_t helper_fadd(CPUMBState *env, uint32_t a, uint32_t b)
{
CPU_FloatU fd, fa, fb;
int flags;
set_float_exception_flags(0, &env->fp_status);
fa.l = a;
fb.l = b;
fd.f = float32_add(fa.f, fb.f, &env->fp_status);
flags = get_float_exception_flags(&env->fp_status);
update_fpu_flags(env, flags);
return fd.l;
}
uint32_t helper_frsub(CPUMBState *env, uint32_t a, uint32_t b)
{
CPU_FloatU fd, fa, fb;
int flags;
set_float_exception_flags(0, &env->fp_status);
fa.l = a;
fb.l = b;
fd.f = float32_sub(fb.f, fa.f, &env->fp_status);
flags = get_float_exception_flags(&env->fp_status);
update_fpu_flags(env, flags);
return fd.l;
}
uint32_t helper_fmul(CPUMBState *env, uint32_t a, uint32_t b)
{
CPU_FloatU fd, fa, fb;
int flags;
set_float_exception_flags(0, &env->fp_status);
fa.l = a;
fb.l = b;
fd.f = float32_mul(fa.f, fb.f, &env->fp_status);
flags = get_float_exception_flags(&env->fp_status);
update_fpu_flags(env, flags);
return fd.l;
}
uint32_t helper_fdiv(CPUMBState *env, uint32_t a, uint32_t b)
{
CPU_FloatU fd, fa, fb;
int flags;
set_float_exception_flags(0, &env->fp_status);
fa.l = a;
fb.l = b;
fd.f = float32_div(fb.f, fa.f, &env->fp_status);
flags = get_float_exception_flags(&env->fp_status);
update_fpu_flags(env, flags);
return fd.l;
}
uint32_t helper_fcmp_un(CPUMBState *env, uint32_t a, uint32_t b)
{
CPU_FloatU fa, fb;
uint32_t r = 0;
fa.l = a;
fb.l = b;
if (float32_is_signaling_nan(fa.f, &env->fp_status) ||
float32_is_signaling_nan(fb.f, &env->fp_status)) {
update_fpu_flags(env, float_flag_invalid);
r = 1;
}
if (float32_is_quiet_nan(fa.f, &env->fp_status) ||
float32_is_quiet_nan(fb.f, &env->fp_status)) {
r = 1;
}
return r;
}
uint32_t helper_fcmp_lt(CPUMBState *env, uint32_t a, uint32_t b)
{
CPU_FloatU fa, fb;
int r;
int flags;
set_float_exception_flags(0, &env->fp_status);
fa.l = a;
fb.l = b;
r = float32_lt(fb.f, fa.f, &env->fp_status);
flags = get_float_exception_flags(&env->fp_status);
update_fpu_flags(env, flags & float_flag_invalid);
return r;
}
uint32_t helper_fcmp_eq(CPUMBState *env, uint32_t a, uint32_t b)
{
CPU_FloatU fa, fb;
int flags;
int r;
set_float_exception_flags(0, &env->fp_status);
fa.l = a;
fb.l = b;
r = float32_eq_quiet(fa.f, fb.f, &env->fp_status);
flags = get_float_exception_flags(&env->fp_status);
update_fpu_flags(env, flags & float_flag_invalid);
return r;
}
uint32_t helper_fcmp_le(CPUMBState *env, uint32_t a, uint32_t b)
{
CPU_FloatU fa, fb;
int flags;
int r;
fa.l = a;
fb.l = b;
set_float_exception_flags(0, &env->fp_status);
r = float32_le(fa.f, fb.f, &env->fp_status);
flags = get_float_exception_flags(&env->fp_status);
update_fpu_flags(env, flags & float_flag_invalid);
return r;
}
uint32_t helper_fcmp_gt(CPUMBState *env, uint32_t a, uint32_t b)
{
CPU_FloatU fa, fb;
int flags, r;
fa.l = a;
fb.l = b;
set_float_exception_flags(0, &env->fp_status);
r = float32_lt(fa.f, fb.f, &env->fp_status);
flags = get_float_exception_flags(&env->fp_status);
update_fpu_flags(env, flags & float_flag_invalid);
return r;
}
uint32_t helper_fcmp_ne(CPUMBState *env, uint32_t a, uint32_t b)
{
CPU_FloatU fa, fb;
int flags, r;
fa.l = a;
fb.l = b;
set_float_exception_flags(0, &env->fp_status);
r = !float32_eq_quiet(fa.f, fb.f, &env->fp_status);
flags = get_float_exception_flags(&env->fp_status);
update_fpu_flags(env, flags & float_flag_invalid);
return r;
}
uint32_t helper_fcmp_ge(CPUMBState *env, uint32_t a, uint32_t b)
{
CPU_FloatU fa, fb;
int flags, r;
fa.l = a;
fb.l = b;
set_float_exception_flags(0, &env->fp_status);
r = !float32_lt(fa.f, fb.f, &env->fp_status);
flags = get_float_exception_flags(&env->fp_status);
update_fpu_flags(env, flags & float_flag_invalid);
return r;
}
uint32_t helper_flt(CPUMBState *env, uint32_t a)
{
CPU_FloatU fd, fa;
fa.l = a;
fd.f = int32_to_float32(fa.l, &env->fp_status);
return fd.l;
}
uint32_t helper_fint(CPUMBState *env, uint32_t a)
{
CPU_FloatU fa;
uint32_t r;
int flags;
set_float_exception_flags(0, &env->fp_status);
fa.l = a;
r = float32_to_int32(fa.f, &env->fp_status);
flags = get_float_exception_flags(&env->fp_status);
update_fpu_flags(env, flags);
return r;
}
uint32_t helper_fsqrt(CPUMBState *env, uint32_t a)
{
CPU_FloatU fd, fa;
int flags;
set_float_exception_flags(0, &env->fp_status);
fa.l = a;
fd.l = float32_sqrt(fa.f, &env->fp_status);
flags = get_float_exception_flags(&env->fp_status);
update_fpu_flags(env, flags);
return fd.l;
}
uint32_t helper_pcmpbf(uint32_t a, uint32_t b)
{
unsigned int i;
uint32_t mask = 0xff000000;
for (i = 0; i < 4; i++) {
if ((a & mask) == (b & mask))
return i + 1;
mask >>= 8;
}
return 0;
}
void helper_memalign(CPUMBState *env, target_ulong addr,
uint32_t dr, uint32_t wr,
uint32_t mask)
{
if (addr & mask) {
qemu_log_mask(CPU_LOG_INT,
"unaligned access addr=" TARGET_FMT_lx
" mask=%x, wr=%d dr=r%d\n",
addr, mask, wr, dr);
env->ear = addr;
env->esr = ESR_EC_UNALIGNED_DATA | (wr << 10) | (dr & 31) << 5;
if (mask == 3) {
env->esr |= 1 << 11;
}
if (!(env->msr & MSR_EE)) {
return;
}
helper_raise_exception(env, EXCP_HW_EXCP);
}
}
void helper_stackprot(CPUMBState *env, target_ulong addr)
{
if (addr < env->slr || addr > env->shr) {
qemu_log_mask(CPU_LOG_INT, "Stack protector violation at "
TARGET_FMT_lx " %x %x\n",
addr, env->slr, env->shr);
env->ear = addr;
env->esr = ESR_EC_STACKPROT;
helper_raise_exception(env, EXCP_HW_EXCP);
}
}
#if !defined(CONFIG_USER_ONLY)
/* Writes/reads to the MMU's special regs end up here. */
uint32_t helper_mmu_read(CPUMBState *env, uint32_t ext, uint32_t rn)
{
return mmu_read(env, ext, rn);
}
void helper_mmu_write(CPUMBState *env, uint32_t ext, uint32_t rn, uint32_t v)
{
mmu_write(env, ext, rn, v);
}
void mb_cpu_transaction_failed(CPUState *cs, hwaddr physaddr, vaddr addr,
unsigned size, MMUAccessType access_type,
int mmu_idx, MemTxAttrs attrs,
MemTxResult response, uintptr_t retaddr)
{
MicroBlazeCPU *cpu;
CPUMBState *env;
qemu_log_mask(CPU_LOG_INT, "Transaction failed: vaddr 0x%" VADDR_PRIx
" physaddr 0x" TARGET_FMT_plx " size %d access type %s\n",
addr, physaddr, size,
access_type == MMU_INST_FETCH ? "INST_FETCH" :
(access_type == MMU_DATA_LOAD ? "DATA_LOAD" : "DATA_STORE"));
cpu = MICROBLAZE_CPU(cs);
env = &cpu->env;
cpu_restore_state(cs, retaddr, true);
if (!(env->msr & MSR_EE)) {
return;
}
env->ear = addr;
if (access_type == MMU_INST_FETCH) {
if ((env->pvr.regs[2] & PVR2_IOPB_BUS_EXC_MASK)) {
env->esr = ESR_EC_INSN_BUS;
helper_raise_exception(env, EXCP_HW_EXCP);
}
} else {
if ((env->pvr.regs[2] & PVR2_DOPB_BUS_EXC_MASK)) {
env->esr = ESR_EC_DATA_BUS;
helper_raise_exception(env, EXCP_HW_EXCP);
}
}
}
#endif